Coupling



FIG. 1 is a top rear perspective view of a coupling showing the claimeddesign; and,

FIG. 2 is a right side view thereof.

The broken lines in the drawings illustrate portions of the couplingthat form no part of the claimed design.

Portions of the coupling not shown in the figures form no part of theclaimed design.

CLAIM The ornamental design for a coupling, as shown and described.